c5cc491e-7119-4500-b05a-e5e34274438f eng utf8 dataset dataset NERC EDS UK Polar Data Centre +44 (0)1223 221400 British Antarctic Survey, High Cross, Madingley Road Cambridge Cambridgeshire CB3 0ET United Kingdom polardatacentre@bas.ac.uk https://www.bas.ac.uk/team/business-teams/information-services/uk-polar-data-centre/ information pointOfContact 2021-06-24 ISO 19115 Geographic Information - Metadata ISO 19115:2003(E) European Petroleum Survey Group (EPSG) Geodetic Parameter Registry 2008-11-12 publication European Petroleum Survey Group EPSGadministrator@iogp.org https://www.epsg-registry.org/ EPSG Geodetic Parameter Dataset The EPSG Geodetic Parameter Dataset is a structured dataset of Coordinate Reference Systems and Coordinate Transformations, accessible through this online registry. information publisher urn:ogc:def:crs:EPSG::3031 6.18.3 Kilometre and sub-kilometre scale atmosphere-only model simulations using the Met Office Unified Model of a foehn wind event over the Larsen C Ice Shelf, Antarctic Peninsula on 27 January 2011 2021-06-24 creation 2021-06-24 revision 2021-06-24 publication 2021-06-24 released 1.0 https://doi.org/10.5285/c5cc491e-7119-4500-b05a-e5e34274438f doi GB/NERC/BAS/PDC/01513 https://data.bas.ac.uk/ NE/G014124/1 award Please cite this item as: Orr, A., & Phillips, T. (2021). Kilometre and sub-kilometre scale atmosphere-only model simulations using the Met Office Unified Model of a foehn wind event over the Larsen C Ice Shelf, Antarctic Peninsula on 27 January 2011 (Version 1.0) [Data set]. NERC EDS UK Polar Data Centre. https://doi.org/10.5285/c5cc491e-7119-4500-b05a-e5e34274438f Firstly, simulations of surface pressure, 10 m zonal wind speed, 10 m meridional wind speed, 1.5 m air temperature, and 1.5 m specific humidity over the Larsen C Ice Shelf for the duration of the OFCAP (Orographic Flows and the Climate of the Antarctic Peninsula) field campaign from 8 January 2011 to 8 February 2011 were conducted using the regional atmosphere-only configuration of the Met Office Unified Model (MetUM) at 4 km grid spacing by the British Antarctic Survey, Cambridge, UK. The datasets produced were necessary to compare with corresponding measurements derived from five Automatic Weather Stations (AWSs) distributed across the Larsen C Ice Shelf to evaluate the main biases in the simulations. Secondly, further MetUM simulations at grid spacings of 1.5 and 0.5 km of a foehn wind event that occurred on 27 January 2011 were conducted, with the datasets produced used to compare results at 4, 1.5 and 0.5 km grid spacing and examine whether the added benefit of sub-kilometre scale grid spacing improves the model representation of foehn winds. Thirdly, a simulation of the foehn wind event on 27 January 2011 using the MetUM at 4 km grid spacing but replacing the 'sharp' stability function used by the boundary layer scheme with the 'long-tail' stability function were also conducted, with the dataset produced used to examine the impact of stronger turbulent mixing for statically stable conditions on the model representation of foehn winds. Funding was provided by NERC grant NE/G014124/1. No credit. completed Orr, Andrew British Antarctic Survey Researcher author Phillips, Tony British Antarctic Survey Researcher author NERC EDS UK Polar Data Centre +44 (0)1223 221400 British Antarctic Survey, High Cross, Madingley Road Cambridge Cambridgeshire CB3 0ET United Kingdom PDCServiceDesk@bas.ac.uk https://www.bas.ac.uk/team/business-teams/information-services/uk-polar-data-centre/ information pointOfContact asNeeded completed EARTH SCIENCE > Atmosphere > Atmospheric Winds theme Global Change Master Directory (GCMD) Science Keywords 2026-01-27 publication 23 Global Change Data Center, Science and Exploration Directorate, Goddard Space Flight Center (GSFC) National Aeronautics and Space Administration (NASA) Greenbelt MD United States of America https://earthdata.nasa.gov/about/gcmd/global-change-master-directory-gcmd-keywords Global Change Master Directory (GCMD) Keywords The information provided on this page seeks to define how the GCMD Keywords are structured, used and accessed. It also provides information on how users can participate in the further development of the keywords. information publisher Antarctic Peninsula Foehn winds/jets Kilometre and sub-kilometre grid scales Larsen C Ice Shelf MetUM Regional atmospheric model theme Larsen C Ice Shelf, Antarctic Peninsula Antarctica place Atmospheric conditions theme GEMET - INSPIRE themes, version 1.0 2021-01-06 revision otherRestrictions no limitations to public access otherRestrictions no limitations license Open Government Licence v3.0 otherRestrictions This data is governed by the NERC Data Policy: https://www.ukri.org/who-we-are/nerc/our-policies-and-standards/nerc-data-policy/ otherRestrictions This data is governed by the NERC data policy and supplied under Open Government Licence v.3 url url crossReference url url crossReference textTable eng utf8 climatologyMeteorologyAtmosphere -75.964 -52.142 -72.97 -62.81 2011-01-08 2011-02-09 0.0 5612.0 urn:ogc:def:crs:EPSG::5714 MSL height Not specific to any location or epoch. Hydrography. It is recommended that careful attention be paid to the contents of any data, and that the author be contacted with any questions regarding appropriate use. If you find any errors or omissions, please report them to polardatacentre@bas.ac.uk. NERC EDS UK Polar Data Centre +44 (0)1223 221400 British Antarctic Survey, High Cross, Madingley Road Cambridge Cambridgeshire CB3 0ET United Kingdom PDCServiceDesk@bas.ac.uk https://www.bas.ac.uk/team/business-teams/information-services/uk-polar-data-centre/ information distributor application/x-hdf application/netcdf bytes 1825361101 https://ramadda.data.bas.ac.uk/repository/entry/show?entryid=c5cc491e-7119-4500-b05a-e5e34274438f WWW:LINK-1.0-http--link Get Data Download data download bytes 1825361101 https://ramadda.data.bas.ac.uk/repository/entry/show?entryid=c5cc491e-7119-4500-b05a-e5e34274438f WWW:LINK-1.0-http--link Get Data Download data download dataset Methodology: We carried out a high-resolution atmosphere-only model simulation of the Larsen C Ice Shelf and surrounding area from 8 January 2011 to 8 February 2011, using the nested configuration of version 11.1 of the UK Met Office Unified Model (MetUM). Three nested model domains at horizontal resolutions of 4, 1.5 and 0.5 km are used. The outer 4 km model domain covers the Antarctic Peninsula and the Larsen C Ice Shelf (domain size of 220 × 220 grid points), while the two additional (one way nested) 1.5 and 0.5 km model domains cover the northern Antarctic Peninsula and Larsen C Ice Shelf (domain size of 450 × 450 and 1000 × 1000 grid points, respectively). Boundary conditions for the 1.5 km (0.5 km) model are derived from the 4 km (1.5 km) model. All three models employ 70 vertical levels (going up to 40 km), which are terrain-following near the surface, with 16 levels below 1000 m and a lowest model level at ~5 m above the surface. The orography used by the 4, 1.5 and 0.5 km models is derived from the high-resolution (200 m) Radarsat Antarctic Modelling Project (RAMP) digital elevation model. Due to the very steep terrain, the 4 and 1.5 km (0.5 km) orography was smoothed by convolution with a normalised 2-d Gaussian kernel with standard deviation of 0.6 grid points (0.8485 grid points). The coastline and ice shelf extent are taken from the Scientific Committee on Antarctic Research (SCAR) Antarctic Digital Database. The science configuration of the dynamics and physics schemes used by the nested models was the mid-latitude regional atmosphere configuration (RA1-M). The 4 km model is nested within a 12 km version of the model (domain size of 150 × 150 grid points), which has a much larger limited area domain encompassing the whole of the Antarctic Peninsula and the surrounding ocean (not shown). The required start data and boundary conditions for the 12 km model are provided by the global model configuration of the MetUM at N320 resolution (domain size of 640 × 480 grid points, equivalent to a horizontal resolution of ~40 km), which is initialised by ERA-Interim reanalysis. The MetUM 4 km model was run twice daily at 00 UTC and 12 UTC from 8 January 2011 to 8 February 2011 for 24 h, with output saved at T+15, T+18, T+21 and T+24 h. Earlier output was discarded as spin-up, with the remaining part of the forecasts concatenated together to form a continuous time-series from 15 UTC 8 January 2011 to 24 UTC 8 February 2011. The computationally expensive MetUM 1.5 km and 0.5 km models were only run to obtain output for 27 January 2011, i.e., coinciding with the foehn event that occurred at this time. A further sensitivity experiment was conducted for 27 January using the MetUM 4 km model but replacing the 'sharp' stability function with the 'long-tail' stability function for the boundary layer scheme, i.e., to examine the impact of stronger turbulent mixing for statically stable conditions. Data collection: The model used was version 11.1 of the Met Office Unified Model. Data quality: Examination of the model output showed that: i) the features commonly associated with foehn winds, such a leeside hydraulic jump, and enhanced leeside warming, were comparatively insensitive to resolution in the 4 to 0.5 km range, although the 0.5 km simulation shows a slightly sharper and larger hydraulic jump, ii) during the foehn wind event, the simulated near-surface air temperature over the Larsen C Ice Shelf was characterised by a both a large nocturnal cold bias of around 10°C and a much too strong low-level temperature inversion, with neither representation improving with increased resolution, and iii) the simulation of fine-scale foehn jets over the Larsen C Ice Shelf during the foehn event showed considerable dependence on grid spacing, although no evidence of convergence at higher resolution. asNeeded completed